The present invention relates generally to printing to a label media using a label printer. In one aspect, the invention relates to a label printer that includes a registration assembly for registering a print head to a registration device. In another aspect, the invention relates to a method for printing a dot line to a label media using the registration assembly.
Electronic label printing machines are often used to generate adhesive labels having images (e.g., indicia, graphics, art, specialized instructions, warnings, slogans, advertising, etc.) to facilitate identification, tracking and pricing of goods. Such label printers typically include: a print head, an assembly (e.g., a label media cartridge) for conveniently supplying or inserting a label media (also called a label media supply) into the printer so that the label media can be fed past the print head in order to be printed, a microprocessor, a read-only memory (ROM) programmed with appropriate instructions therein to operate the microprocessor, a random access memory (RAM), a keyboard with letter, number, and function keys for entry of alphanumeric information requisite to printing the indicia on the label media, and a visual display such as a light emitting diode (xe2x80x9cLEDxe2x80x9d) or liquid crystal display (xe2x80x9cLCDxe2x80x9d) screen to convey information to a machine operator. These components function together to achieve the end goal of creating high quality and accurate labels from the label media using the electronic label printing machine.
Labels are made from a label media. The label media itself typically is made up of a roll of pressure sensitive tape that is attached, typically along a side containing an adhesive, to a continuous support roll of release liner material. The label media is fed in a media direction along a media path through the label printer. Discrete labels are formed by cutting the label media. Complex label shapes can be obtained by plotter cutting the tape layer only of the label media. The label media can be end cut (i.e., cutting through the tape and the release liner layers) or portioned into an end cut label media portion in order to obtain as many discrete labels in a continuous row as is desired. In other words, one or more than one discrete label can reside on an end cut label media portion. An end cutting operation can occur with or without a plotter cutting operation first having taken place. Following label media cutting, the discrete labels can be removed from the release liner and attached, as appropriate, to the particular application requiring identification. Since there are many types of label applications, there are many combinations of tape and release liners that can provide labels of varying sizes, colors, formats, and characteristics.
One type of label printer employs a thermal transfer print head. In general, the use of thermal print heads in label printers has increased as the quality and accuracy of thermal print heads has improved. Thermal transfer printing uses a heat-generating print head to transfer ink, or the like, from a thermal transfer ribbon to a label media to form a label image on the media. A microprocessor determines a sequence of individual thermal, typically resistive, print head elements to be selectively heated or energized. Energizing the sequence of elements in turn heats the ribbon so as to transfer the ink from the ribbon, creating the desired image on the label media, and specifically, on the label tape. The label printer can be fed label media from a label media source. Simultaneously, a thermal transfer ribbon can be fed from a ribbon source. While the label media runs between the print head and a support (platen) roller, the transfer ribbon can run between the print head and the support roller. Thus, the label media and the transfer ribbon can run together in an overlay relationship between the print head and the support roller.
When it is desired to print a color image on a label media, it is generally required to print the image by passing the label media several times past the print head. To accomplish each pass, the label media is fed, retracted, and then re-fed again past the thermal print head. With each pass, a different primary color, for example, in a traditional color scheme, cyan, magenta, yellow, and black, is printed from a continuous ink ribbon onto the label media using the print head. In this manner, based on the amount of each color printed, a composite color image can be printed onto a label media.
It is continually desirable to improve the functionality, performance and/or efficiency of various components, or combinations of components (also sometimes called xe2x80x9cassembliesxe2x80x9d or xe2x80x9csubassembliesxe2x80x9d) that make up label printers. For example, it would be desirable to improve the process of cutting label media in label printers.
Thermal printing requires physical contact between the print head and, in particular, the thermal printing elements, and the label media for printing to occur. The physical contact results in a force being applied from the print head to the media. There are many varieties of label media that can be used. Each specific media requires a unique force in order to accomplish the requisite physical contact for appropriate printing to occur.
Not only is it necessary to apply the proper force of the print head to the media, but the force must be applied at the proper location for appropriate printing to occur. Therefore, registration, or proper alignment, between the print head and the label media is required. It is always desirable to accomplish this registration in as simple a manner (e.g., fewest parts or components) as possible. Contemporaneously, it is necessary to be able to accomplish this registration for all of the conditions (e.g., different label media types, different forces at which printing occurs for each specific label media type, and the like) encountered during printing.
Thus, it would be advantageous, especially in label printers designed for use with a variety of label media types, to be able to accomplish printing to a label media such that the printing is in registration, and moreover, in a manner that can accommodate adjustment or varying of the load that is applied to the label media according to the specific label media used. It would be further desirable if such printing were accomplished in an efficient and cost-effective manner.
The present invention generally provides a label printer dot line registration assembly that overcomes the aforementioned problems.
According to one aspect, provided herein is, in a label printer having a cover portion frame and a base portion frame, a label printer registration assembly comprising: a registration device securable to the base portion frame of the label printer, and a print head assembly mountable to the cover portion frame of the label printer, the print head assembly comprising: a variably loadable print head for printing to a label media; and a registration face attached to the print head; wherein the registration face is engageable with the registration device to maintain registration between the print head and the registration device.
According to another aspect, provided herein is a method of printing to a label media, the method comprising: providing a dot line registration assembly, the dot line registration assembly including: a registration roller securable to a base portion frame of a label printer; and a print head assembly mountable to a cover portion frame of the label printer, the print head assembly including: a variably loadable, thermal print head for printing the registered dot line to the label media; and registration face attached to the print head; engaging the registration face with the registration device so as to achieve and maintain dot line registration; loading the variably loadable print head to a label media-specific load to achieve loaded registration between the print head and the registration roller; and thermally printing, at the media-specific load, a dot line to the label media, using the print head.
Various other aspects, features, objects and advantages of the present invention will be made apparent from the following detailed description and the drawings.